Effects of Soil Organic Matter Properties and Microbial Community Composition on Enzyme Activities in Cryoturbated Arctic Soils

Enzyme-mediated decomposition of soil organic matter (SOM) is controlled, amongst other factors, by organic matter properties and by the microbial decomposer community present. Since microbial community composition and SOM properties are often interrelated and both change with soil depth, the drivers of enzymatic decomposition are hard to dissect. We investigated soils from three regions in the Siberian Arctic, where carbon rich topsoil material has been incorporated into the subsoil (cryoturbation). We took advantage of this subduction to test if SOM properties shape microbial community composition, and to identify controls of both on enzyme activities. We found that microbial community composition (estimated by phospholipid fatty acid analysis), was similar in cryoturbated material and in surrounding subsoil, although carbon and nitrogen contents were similar in cryoturbated material and topsoils. This suggests that the microbial community in cryoturbated material was not well adapted to SOM properties. We also measured three potential enzyme activities (cellobiohydrolase, leucine-amino-peptidase and phenoloxidase) and used structural equation models (SEMs) to identify direct and indirect drivers of the three enzyme activities. The models included microbial community composition, carbon and nitrogen contents, clay content, water content, and pH. Models for regular horizons, excluding cryoturbated material, showed that all enzyme activities were mainly controlled by carbon or nitrogen. Microbial community composition had no effect. In contrast, models for cryoturbated material showed that enzyme activities were also related to microbial community composition. The additional control of microbial community composition could have restrained enzyme activities and furthermore decomposition in general. The functional decoupling of SOM properties and microbial community composition might thus be one of the reasons for low decomposition rates and the persistence of 400 Gt carbon stored in cryoturbated material.

Buholzer, Alois / Joller-Graf Klaus / Kummer Wyss, Annemarie / Zobrist, Bruno (Hrsg.): Kompetenzprofil zum Umgang mit heterogenen Lerngruppen. Wien, Zürich, Berlin, Münster: LIT Verlag 2012 [Rezension]

Rezension von: Buholzer, Alois / Joller-Graf Klaus / Kummer Wyss, Annemarie / Zobrist, Bruno (Hrsg.): Kompetenzprofil zum Umgang mit heterogenen Lerngruppen, Wien, Zürich, Berlin, Münster: LIT Verlag 2012 (77 S.; ISBN 978-3-643-80084-8)

Peter Dehnbostel: Betriebliche Bildungsarbeit, Kompetenzbasierte Aus- und Weiterbildung im Betrieb. Baltmannsweiler: Schneider Verlag Hohengehren 2010 [Rezension]

Rezension von: Peter Dehnbostel: Betriebliche Bildungsarbeit, Kompetenzbasierte Aus- und Weiterbildung im Betrieb, Baltmannsweiler: Schneider Verlag Hohengehren 2010 (146 S.; ISBN 978-3-8340-0699-8)

Transcriptome-Wide Mapping of Pea Seed Ageing Reveals a Pivotal Role for Genes Related to Oxidative Stress and Programmed Cell Death

Understanding of seed ageing, which leads to viability loss during storage, is vital for ex situ plant conservation and agriculture alike. Yet the potential for regulation at the transcriptional level has not been fully investigated. Here, we studied the relationship between seed viability, gene expression and glutathione redox status during artificial ageing of pea (Pisum sativum) seeds. Transcriptome-wide analysis using microarrays was complemented with qRT-PCR analysis of selected genes and a multilevel analysis of the antioxidant glutathione. Partial degradation of DNA and RNA occurred from the onset of artificial ageing at 60% RH and 50 degrees C, and transcriptome profiling showed that the expression of genes associated with programmed cell death, oxidative stress and protein ubiquitination were altered prior to any sign of viability loss. After 25 days of ageing viability started to decline in conjunction with progressively oxidising cellular conditions, as indicated by a shift of the glutathione redox state towards more positive values (>-190 mV). The unravelling of the molecular basis of seed ageing revealed that transcriptome reprogramming is a key component of the ageing process, which influences the progression of programmed cell death and decline in antioxidant capacity that ultimately lead to seed viability loss.

Wolfgang Einsiedler (Hrsg.): Unterrichtsentwicklung und Didaktische Entwicklungsforschung. Bad Heilbrunn: Klinkhardt 2011 [Rezension]

Rezension von: Wolfgang Einsiedler (Hrsg.): Unterrichtsentwicklung und Didaktische Entwicklungsforschung, Bad Heilbrunn: Klinkhardt 2011 (184 S.; ISBN 978-3-7815-1794-3)

Cell- and Tissue-Specific Transcriptome Analyses of Medicago truncatula Root Nodules

Legumes have the unique ability to host nitrogen-fixing Rhizobium bacteria as symbiosomes inside root nodule cells. To get insight into this key process, which forms the heart of the endosymbiosis, we isolated specific cells/tissues at different stages of symbiosome formation from nodules of the model legume Medicago truncatula using laser-capture microdissection. Next, we determined their associated expression profiles using Affymetrix Medicago GeneChips. Cells were collected from the nodule infection zone divided into a distal (where symbiosome formation and division occur) and proximal region (where symbiosomes are mainly differentiating), as well as infected cells from the fixation zone containing mature nitrogen fixing symbiosomes. As non-infected cells/tissue we included nodule meristem cells and uninfected cells from the fixation zone. Here, we present a comprehensive gene expression map of an indeterminate Medicago nodule and selected genes that show specific enriched expression in the different cells or tissues. Validation of the obtained expression profiles, by comparison to published gene expression profiles and experimental verification, indicates that the data can be used as digital "in situ''. This digital "in situ'' offers a genome-wide insight into genes specifically associated with subsequent stages of symbiosome and nodule cell development, and can serve to guide future functional studies.

Miriam Hellrung: Lehrerhandeln im individualisierten Unterricht, Entwicklungsaufgaben und ihre Bewältigung. Opladen / Farmington Hills: Verlag Barbara Budrich 2010 [Rezension]

Rezension von: Miriam Hellrung: Lehrerhandeln im individualisierten Unterricht, Entwicklungsaufgaben und ihre Bewältigung, Opladen / Farmington Hills: Verlag Barbara Budrich 2010 (276 S.; ISBN 978-3-86649-338-4)

Awareness and Learning in Participatory Noise Sensing

The development of ICT infrastructures has facilitated the emergence of new paradigms for looking at society and the environment over the last few years. Participatory environmental sensing, i.e. directly involving citizens in environmental monitoring, is one example, which is hoped to encourage learning and enhance awareness of environmental issues. In this paper, an analysis of the behaviour of individuals involved in noise sensing is presented. Citizens have been involved in noise measuring activities through the WideNoise smartphone application. This application has been designed to record both objective (noise samples) and subjective (opinions, feelings) data. The application has been open to be used freely by anyone and has been widely employed worldwide. In addition, several test cases have been organised in European countries. Based on the information submitted by users, an analysis of emerging awareness and learning is performed. The data show that changes in the way the environment is perceived after repeated usage of the application do appear. Specifically, users learn how to recognise different noise levels they are exposed to. Additionally, the subjective data collected indicate an increased user involvement in time and a categorisation effect between pleasant and less pleasant environments.

Jens Oliver Krüger: Pädagogische Ironie – Ironische Pädagogik, Diskursanalytische Untersuchungen. Paderborn: Schöningh 2011 [Rezension]

Rezension von: Jens Oliver Krüger: Pädagogische Ironie – Ironische Pädagogik, Diskursanalytische Untersuchungen, Paderborn: Schöningh 2011 (227 S.; ISBN 978-3-506-77062-2)

How Psychiatry Journals Support the Unbiased Translation of Clinical Research. A Cross-Sectional Study of Editorial Policies

Introduction: Reporting guidelines (e. g. CONSORT) have been developed as tools to improve quality and reduce bias in reporting research findings. Trial registration has been recommended for countering selective publication. The International Committee of Medical Journal Editors (ICMJE) encourages the implementation of reporting guidelines and trial registration as uniform requirements (URM). For the last two decades, however, biased reporting and insufficient registration of clinical trials has been identified in several literature reviews and other investigations. No study has so far investigated the extent to which author instructions in psychiatry journals encourage following reporting guidelines and trial registration. Method: Psychiatry Journals were identified from the 2011 Journal Citation Report. Information given in the author instructions and during the submission procedure of all journals was assessed on whether major reporting guidelines, trial registration and the ICMJE's URM in general were mentioned and adherence recommended. Results: We included 123 psychiatry journals (English and German language) in our analysis. A minority recommend or require 1) following the URM (21%), 2) adherence to reporting guidelines such as CONSORT, PRISMA, STROBE (23%, 7%, 4%), or 3) registration of clinical trials (34%). The subsample of the top-10 psychiatry journals (ranked by impact factor) provided much better but still improvable rates. For example, 70% of the top-10 psychiatry journals do not ask for the specific trial registration number. Discussion: Under the assumption that better reported and better registered clinical research that does not lack substantial information will improve the understanding, credibility, and unbiased translation of clinical research findings, several stakeholders including readers (physicians, patients), authors, reviewers, and editors might benefit from improved author instructions in psychiatry journals. A first step of improvement would consist in requiring adherence to the broadly accepted reporting guidelines and to trial registration.

Rebecca Lazarides / Angela Ittel (Hrsg.): Differenzierung im mathematisch-naturwissenschaftlichen Unterricht, Implikationen für Theorie und Praxis. Bad Heilbrunn: Klinkhardt 2012 [Rezension]

Rezension von: Rebecca Lazarides / Angela Ittel (Hrsg.): Differenzierung im mathematisch-naturwissenschaftlichen Unterricht, Implikationen für Theorie und Praxis, Bad Heilbrunn: Klinkhardt 2012 (232 S.; ISBN 978-3-7815-1845-2)

Lisa Pfahl: Techniken der Behinderung, Der deutsche Lernbehindertendiskurs, die Sonderschule und ihre Auswirkungen auf Bildungsbiografien. Bielefeld: transcript 2011 [Rezension]

Rezension von: Lisa Pfahl: Techniken der Behinderung, Der deutsche Lernbehindertendiskurs, die Sonderschule und ihre Auswirkungen auf Bildungsbiografien, Bielefeld: transcript 2011 (276 S.; ISBN 978-3-8376-1532-6)

Future Bloom and Blossom Frost Risk for Malus domestica Considering Climate Model and Impact Model Uncertainties

The future bloom and risk of blossom frosts for Malus domestica were projected using regional climate realizations and phenological (= impact) models. As climate impact projections are susceptible to uncertainties of climate and impact models and model concatenation, the significant horizon of the climate impact signal was analyzed by applying 7 impact models, including two new developments, on 13 climate realizations of the IPCC emission scenario A1B. Advancement of phenophases and a decrease in blossom frost risk for Lower Saxony (Germany) for early and late ripeners was determined by six out of seven phenological models. Single model/single grid point time series of bloom showed significant trends by 2021-2050 compared to 1971-2000, whereas the joint signal of all climate and impact models did not stabilize until 2043. Regarding blossom frost risk, joint projection variability exceeded the projected signal. Thus, blossom frost risk cannot be stated to be lower by the end of the 21st century despite a negative trend. As a consequence it is however unlikely to increase. Uncertainty of temperature, blooming date and blossom frost risk projection reached a minimum at 2078-2087. The projected phenophases advanced by 5.5 d K-1, showing partial compensation of delayed fulfillment of the winter chill requirement and faster completion of the following forcing phase in spring. Finally, phenological model performance was improved by considering the length of day.

Pilz, Matthias / Berger, Susanne / Canning, Roy (Hrsg.): Fit for business, Pre vocational education in European Schools. Heidelberg: Springer 2012 [Rezension]

Rezension von: Pilz, Matthias / Berger, Susanne / Canning, Roy (Hrsg.): Fit for business, Pre vocational education in European Schools, Heidelberg: Springer 2012 (211 S.; ISBN 978-3-531-18383-1)

Coffee Berry Borer Joins Bark Beetles in Coffee Klatch

Unanswered key questions in bark beetle-plant interactions concern host finding in species attacking angiosperms in tropical zones and whether management strategies based on chemical signaling used for their conifer-attacking temperate relatives may also be applied in the tropics. We hypothesized that there should be a common link in chemical signaling mediating host location by these Scolytids. Using laboratory behavioral assays and chemical analysis we demonstrate that the yellow-orange exocarp stage of coffee berries, which attracts the coffee berry borer, releases relatively high amounts of volatiles including conophthorin, chalcogran, frontalin and sulcatone that are typically associated with Scolytinae chemical ecology. The green stage of the berry produces a much less complex bouquet containing small amounts of conophthorin but no other compounds known as bark beetle semiochemicals. In behavioral assays, the coffee berry borer was attracted to the spiroacetals conophthorin and chalcogran, but avoided the monoterpenes verbenone and a-pinene, demonstrating that, as in their conifer-attacking relatives in temperate zones, the use of host and non-host volatiles is also critical in host finding by tropical species. We speculate that microorganisms formed a common basis for the establishment of crucial chemical signals comprising inter-and intraspecific communication systems in both temperate-and tropical-occurring bark beetles attacking gymnosperms and angiosperms.